What is the approximate value of the speed of light in a vacuum?

What is the approximate value of the speed of light in a vacuum?

• A. Approximately 9.8 kilometers per second.
• B. Approximately 3.0 × 10^6 m/s.
• C. Approximately 3.0 × 10^7 m/s.
• D. Approximately 3.0 × 10^8 m/s.

Answer: (D)

The speed of light in a vacuum is a constant: light travels at about 3.0 × 10^8 meters per second. This value is the universal speed limit for anything that carries information or energy, and it’s the same for all light in empty space regardless of color. In materials, light slows down depending on the material’s properties, but in vacuum it is this fixed speed. Among the choices, 3.0 × 10^8 m/s matches light’s speed in empty space. The other numbers don’t fit: 9.8 kilometers per second is the acceleration due to gravity, not light speed; 3.0 × 10^6 m/s and 3.0 × 10^7 m/s are far too small to describe light’s speed.

The speed of light in a vacuum is a constant: light travels at about 3.0 × 10^8 meters per second. This value is the universal speed limit for anything that carries information or energy, and it’s the same for all light in empty space regardless of color. In materials, light slows down depending on the material’s properties, but in vacuum it is this fixed speed.

Among the choices, 3.0 × 10^8 m/s matches light’s speed in empty space. The other numbers don’t fit: 9.8 kilometers per second is the acceleration due to gravity, not light speed; 3.0 × 10^6 m/s and 3.0 × 10^7 m/s are far too small to describe light’s speed.